Samsung ML-2851ND/SEE User manual

DIGITAL LASER PRINTER The keynote of Product
Smallest Duplex Bu lt- n
Mono Laser Pr nter (Low Noise)
- 28ppm(A4) / 30ppm(Ltr)
- PCL6, PS3, 1,200x1,200dpi
- 400MHz proce or
- USB 2.0, N/W (ML-2851ND only)
- 32MB (Max.160MB : factory option)
- 2K Standard, 5K High Yield
- Paper Input: 250 h CST + 1 h MP
- Standard Duplex Printing
- Option : 250 h SCF
ML-2850D
Manual
SERVICE
DIGITAL LASER PRINTER
ML-2850 Series
ML-2850D / ML-2851ND
Bas c Model :ML-2851ND
ML-2851ND/SEE

Sam ung Electronic Co.,Ltd. Aug. 2007
Printed in Korea.
VERSION NO. : 1.00 CODE : 2851-D0SEE
GSPN (Global Service Partner Network)
North America : service.samsungportal.com
Latin America : latin.samsungportal.com
C S : cis.samsungportal.com
Europe : europe.samsungportal.com
China : china.samsungportal.com
Asia : asia.samsungportal.com
Mideast & Africa : mea.samsungportal.com

1. Precaut ons
1.1 Safety Warning 1-1
1.2 Caution for afety 1-2
1.3 ESD Precaution 1-5
2. Product spec and feature
2.1 Product Specification 2-1
2.1.1 Product Overview 2-1
2.1.2 Specification 2-1
2.1.3 Model Compari on Table 2-7
2.2 Summary of Product 2-9
2.2.1 Printer Component 2-9
2.2.2 Sy tem Layout 2-12
2.2.3 Engine H/W Specification 2-17
2.2.4 S/W De cription 2-27
3. D sassembly and Reassembly
3.1 General Precaution on Di a embly 3-1
3.2 U ed Screw Li t 3-2
3.3 Cover Unit 3-3
3.3.1 CASSETTE & Front Cover 3-3
3.3.2 DUPLEX UNIT & COVER-TOP/COVER-REAR 3-4
3.3.3 Cover-Side-LEFT/RIGHT 3-5
3.4 Fu er A 'y 3-6
3.5 LSU(La er Scanning Unit) 3-7
3.6 Drive A 'y 3-8
3.7 Main PBA/SMPS/HVPS 3-9
3.8 HOLDER-PAD Di a embly 3-10
Contents

3.9 Tran fer Roller 3-11
4. Al gnment & Troubleshoot ng
4.1 Alignment and Adju tment 4-1
4.1.1 Sample Pattern 4-1
4.1.2 Control Panel 4-4
4.1.3 Con umable and Replacement Part 4-7
4.1.4 LED Statu Error Me age 4-7
4.1.5 Abnormal Image Printing and Defective Roller 4-8
4.1.6 How to u e DCU 4-9
4.1.7 Paper Jam 4-15
4.1.8 Download & Re et F/W 4-20
4.2 Trouble hooting 4-21
4.2.1 Procedure of Checking the Symptom 4-21
4.2.2 The cau e and olution of Bad image 4-22
4.2.3 The cau e and olution of the bad di charge 4-38
4.2.4 The cau e and olution of the malfunction 4-46
4.2.5 Toner Cartridge Service 4-56
4.2.6 The cau e and olution of bad environment of the oftware 4-58
5. Exploded V ews & Parts L st
5.1 Main 5-2
5.2 Top Cover 5-4
5.3 Cover A 'y 5-6
5.4 Front Cover 5-8
5.5 Rear Cover 5-10
5.6 Frame 5-12
5.7 Main Drive 5-17
5.8 Rear Guide 5-19
Cont nued

5.9 Fu er 5-21
5.10 Duplex Unit 5-23
5.11 Ca ette 5-25
5.12 SCF 5-27
6. System D agram
6.1 Block Diagram 6-1
6.2 Connection Dia ram 6-2
7. Reference Informat on
7.1 Tool for Trouble hooting 7-1
7.2 Acronym and Abbreviation 7-2
7.3 Select a location for the printer 7-4
7.4 Sample Te t Pattern 7-5
7.5 LAN (Optional Function) 7-6
7.6 Information of model' code 7-6
7.7 Part Life Cycle Maintenance Table 7-7
7.7.1 Part Life Cycle Maintenance Table 7-7
7.7.2 Toner Cartridge Criterion 7-7
7.8 Model Information 7-8
7.8.1 Under tanding for Model Code 7-8
7.8.2 Under tanding Material Code & Name 7-9
Cont nued

Service Manual
Precautions
1-1
Samsung Electronics
1. Precautions
In order to prevent accidents and to prevent damage to the equipment please read the precautions listed
below carefully before servicing the printer and follow them closely.
1.1 Safety Warning
(1) Only to be serviced by appropriately qualified service engineers.
igh voltages and lasers inside this product are dangerous. This printer should only be serviced by a suitably
trained and qualified service engineer.
(2) Use only Samsung replacement parts
There are no user serviceable parts inside the printer. Do not make any unauthorized changes or
additions to the printer, these could cause the printer to malfunction and create electric shock or fire hazards.
(3) Laser Safety Statement
The Printer is certified in the U.S. to conform to the requirements of D S 21 CFR, chapter 1 Subchapter J for
Class 1(1) laser products, and elsewhere, it is certified as a Class I laser product
conforming to the requirements of IEC 825. Class I laser products are not considered to be hazardous. The
laser system and printer are designed so there is never any human access to laser radiation above a Class I
level during normal operation, user maintenance, or prescribed service condition.
Warning >> Never operate or service the printer with the protective cover removed from Laser/Scanner assembly. The
reflected beam, although invisible, can damage your eyes. When using this product, these basic safety
pre cautions should always be followed to reduce risk of fire, electric shock, and injury to persons.
CAUTION - INVISIBLE LASER RADIATION 
W EN T IS COVER OPEN. 
DO NOT OPEN T IS COVER.
VORSIC T - UNSIC TBARE LASERSTRA LUNG, 
WENN ABDECKUNG GEÖFFNET. 
NIC T DEM STRA L AUSSETZEN.
ATTENTION - RAYONNEMENT LASER INVISIBLE EN CAS 
D’OUVERTURE. EXPOSITION DANGEREUSE 
AU FAISCEAU.
ATTENZIONE - RADIAZIONE LASER INVISIBILE IN CASO DI 
APERTURA. EVITARE L’ESPOSIZIONE AL 
FASCIO.
PRECAUCION - RADIACION LASER IVISIBLE CUANDO SE ABRE. 
EVITAR EXPONERSE AL RAYO.
ADVARSEL. - USYNLIG LASERSTRÅLNING VED ÅBNING, NÅR 
SIKKER EDSBRYDERE ER UDE AF FUNKTION. 
UNDGÅ UDSAETTELSE FOR STRÅLNING.
ADVARSEL. - USYNLIG LASERSTRÅLNING NÅR DEKSEL 
ÅPNES. STIRR IKKE INN I STRÅLEN. 
UNNGÅ EKSPONERING FOR STRÅLEN.
VARNING - OSYNLIG LASERSTRÅLNING NÄR DENNA DEL 
ÄR ÖPPNAD OC SPÄRREN ÄR URKOPPLAD. 
BETRAKTA EJ STRÅLEN. STRÅLEN ÄR FARLIG.
VARO! - AVATTAESSA JA SUOJALUKITUS O ITETTAESSA 
OLET ALTTIINA NÄKYMÄTTÖMÄLLE LASER-
SÄTEILYLLE ÄLÄ KATSO SÄTEESEEN.

Service Manual
Precautions
1-2
Samsung Electronics
1.2 Caution for safety
1.2.1 Toxic material
This product contains toxic materials that could cause illness if ingested.
(1) If the LCD control panel is damaged it is possible for the liquid inside to leak. This liquid is toxic. Contact with the skin
should be avoided, wash any splashes from eyes or skin immediately and contact your doctor. If the liquid gets into
the mouth or is swallowed see a doctor immediately.
(2) Please keep toner cartridges away from children. The toner powder contained in the toner cartridge may be harmful
and if swallowed you should contact a doctor.
1.2.2 Electric Shock and Fire Safety Precautions
Failure to follow the following instructions could cause electric shock or potentially cause a fire.
(1) Use only the correct voltage, failure to do so could damage the printer and potentially cause a fire or electric
shock.
(2) Use only the power cable supplied with the printer. Use of an incorrectly specified cable could cause the cable
to overheat and potentially cause a fire.
(3) Do not overload the power socket, this could lead to overheating of the cables inside the wall and could lead to
a fire.
(4) Do not allow water or other liquids to spill into the printer, this can cause electric shock. Do not allow paper
clips, pins or other foreign objects to fall into the printer these could cause a short circuit leading to an electric
shock or fire hazard..
(5) Never touch the plugs on either end of the power cable with wet hands, this can cause electric shock. When
servicing the printer remove the power plug from the wall socket.
(6) Use caution when inserting or removing the power connector. The power connector must be inserted com-
pletely otherwise a poor contact could cause overheating possibly leading to a fire. When removing the power
connector grip it firmly and pull.
(7) Take care of the power cable. Do not allow it to become twisted, bent sharply round corners or other wise
damaged. Do not place objects on top of the power cable. If the power cable is damaged it could overheat and
cause a fire or exposed cables could cause an electric shock. Replace a damaged power cable immediately,
do not reuse or repair the damaged cable. Some chemicals can attack the coating on the power cable,
weakening the cover or exposing cables causing fire and shock risks.
(8) Ensure that the power sockets and plugs are not cracked or broken in any way. Any such defects should be
repaired immediately. Take care not to cut or damage the power cable or plugs when moving the machine.
(9) Use caution during thunder or lightening storms. Samsung recommends that this machine be disconnected
from the power source when such weather conditions are expected. Do not touch the machine or the power
cord if it is still connected to the wall socket in these weather conditions.
(10) Avoid damp or dusty areas, install the printer in a clean well ventilated location. Do not position the machine
near a humidifier. Damp and dust build up inside the machine can lead to overheating and cause a fire.
(11) Do not position the printer in direct sunlight. This will cause the temperature inside the printer to rise possibly
leading to the printer failing to work properly and in extreme conditions could lead to a fire.
(12) Do not insert any metal objects into the machine through the ventilator fan or other part of the casing, it could
make contact with a high voltage conductor inside the machine and cause an electric shock.

Service Manual
Precautions
1-3
Samsung Electronics
1.2.3 Handling Precautions
The following instructions are for your own personal safety, to avoid injury and so as not to damage the printer
(1) Ensure the printer is installed on a level surface, capable of supporting its weight. ailure to do so could cause
the printer to tip or fall.
(2) The printer contains many rollers, gears and fans. Take great care to ensure that you do not catch your fingers,
hair or clothing in any of these rotating devices.
(3) Do not place any small metal objects, containers of water, chemicals or other liquids close to the printer which if
spilled could get into the machine and cause damage or a shock or fire hazard.
(4) Do not install the machine in areas with high dust or moisture levels, beside on open window or close to a
humidifier or heater. Damage could be caused to the printer in such areas.
(5) Do not place candles, burning cigarettes, etc on the printer, These could cause a fire.
1.2.4 Assembly / Disassembly Precautions
Replace parts carefully, always use Samsung parts. Take care to note the exact location of parts and also
cable routing before dismantling any part of the machine. Ensure all parts and cables are replaced correctly.
Please carry out the following procedures before dismantling the printer or replacing any parts.
(1) Check the contents of the machine memory and make a note of any user settings. These will be erased if the
mainboard or network card is replaced.
(2) Ensure that power is disconnected before servicing or replacing any electrical parts.
(3) Disconnect printer interface cables and power cables.
(4) Only use approved spare parts. Ensure that part number, product name, any voltage, current or temperature
rating are correct.
(5) When removing or re-fitting any parts do not use excessive force, especially when fitting screws into plastic.
(6) Take care not to drop any small parts into the machine.

Service Manual
Precautions
1-4
Samsung Electronics
1.2.5 Disregarding this warning may cause bodily injury
(1) Be careful with the high temperature part.
The fuser unit works at a high temperature. Use caution when working on the printer. Wait for the fuser to cool
down before disassembly.
(2) Do not put finger or hair into the rotating parts.
When operating a printer, do not put hand or hair into the rotating parts (Paper feeding entrance, motor, fan,
etc. . If do, you can get harm.
(3) hen you move the printer.
This printer weighs 7.87kg. Use safe lifting and handling techniques. Use the lifting handles located on each
side of the machine. Back injury could be caused if you do not lift carefully.
(4) Ensure the printer is installed safely.
The printer weighs 7.87Kg, ensure the printer is installed on a level surface, capable of supporting its weight.
Failure to do so could cause the printer to tip or fall possibly causing personal injury or damaging the printer.
(5) Do not install the printer on a sloping or unstable surface. After installation, double check that the printer is stable.
17.35 Ibs.
7.87 Kg

Service Manual
Precautions
1-5
Samsung Electronics
1.3 ESD Precautions
Certain semiconductor devices can be easily damaged by static electricity. Such components are commonly called
“Electrostatically Sensitive (ES) Devices”, or ESDs. Examples of typical ESDs are: integrated circuits, some field
effect transistors, and semiconductor “chip” components.
The techniques outlined below should be followed to help reduce the incidence of component damage caused by
static electricity.
Caution >>Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.
1. Immediately before handling a semiconductor component or semiconductor-equipped assembly, drain off any
electrostatic charge on your body by touching a known earth ground. Alternatively, employ a commercially avail-
able wrist strap device, which should be removed for your personal safety reasons prior to applying power to the
unit under test.
2. After removing an electrical assembly equipped with ESDs, place the assembly on a conductive surface, such as
aluminum or copper foil, or conductive foam, to prevent electrostatic charge buildup in the vicinity of the assem-
bly.
3. Use only a grounded tip soldering iron to solder or desolder ESDs.
4. Use only an “anti-static” solder removal device. Some solder removal devices not classified as “anti-static” can
generate electrical charges sufficient to damage ESDs.
5. Do not use Freon-propelled chemicals. When sprayed, these can generate electrical charges sufficient to dam-
age ESDs.
6. Do not remove a replacement ESD from its protective packaging until immediately before installing it. Most
replacement ESDs are packaged with all leads shorted together by conductive foam, aluminum foil, or a compa-
rable conductive material.
7. Immediately before removing the protective shorting material from the leads of a replacement ESD, touch the pro-
tective material to the chassis or circuit assembly into which the device will be installed.
8. Maintain continuous electrical contact between the ESD and the assembly into which it will be installed, until com-
pletely plugged or soldered into the circuit.
9. Minimize bodily motions when handling unpackaged replacement ESDs. Normal motions, such as the brushing
together of clothing fabric and lifting one’s foot from a carpeted floor, can generate static electricity sufficient to
damage an ESD.

Service Manual
Product spec and feature
2-1
Samsung Electronics
2.1.2 Specifications
Product Specifications are subject to change without notice. See below for product specifications.
2.1.2.1 General Print Engine
ITEM ML-2850D ML-2851ND
Engine Speed Simplex Up to 28 ppm in A4 30 ppm in Letter) Up to 28 ppm in A4 30 ppm in Letter)
Duplex Up to 14 ipm in A4 14.5 ipm in Letter) Up to 14 ipm in A4 14.5 ipm in Letter)
Warmup time From Sleep 15 sec 15 sec
FPOT From Ready 8.5 sec 8.5 sec
From Sleep less than 23.5 sec less than 23.5 sec
Resolution - Up to 1,200 x 1,200 dpi effective output Up to 1,200 x 1,200 dpi effective output
2. Pro uct specification an feature
2.1 Pro uct Specifications
2.1.1 Pro uct Overview
28ppm(A4) / 30ppm(Ltr)
PCL6, PS3, 1,200x1,200dpi
400MHz processor
SB 2.0, N/W (ML-2851ND only)
32MB (Max.160MB : option)
ML-2850D/2851ND
Options:
- 250 sh SCF
2K Standard, 5K High Yield
Paper Input: 250 CST + 1 MP
Standard Duplex Printing
(World Smallest)

Service Manual
Product spec and feature
2-2
Samsung Electronics
2.1.2.2 Controller & S/W
ITEM ML-2850D ML-2851ND
Processor Samsung 400 MHz Samsung 400 MHz
Memory Std. 32 MB 32 MB
Max.160MB option) 160MB option)
Printer Languages - PostScript3, PCL6, SPL, IBM ProPrinter, PostScript3, PCL6, SPL, IBM ProPrinter,
EPSON EPSON
Fonts - 45 scalable, 1 bitmap, 136 PostScript3 fonts 45 scalable, 1 bitmap, 136 PostScript3 fonts
Driver Default Driver SPL SPL
Install SPL, PCL6, PS3 SPL, PCL6, PS3
Supporting OS Windows 2000/XP 32/64bits)/Vista 32/ Windows 2000/XP 32/64bits)/Vista 32/
64bits)/2003 Server 32/64bits) 64bits)/2003 Server 32/64bits)
Various Linux OS: Various Linux OS:
- Red Hat 8~9, - Red Hat 8~9,
- Fedora Core 1~4 - Fedora Core 1~4
- Mandrake 9.2~10.1 - Mandrake 9.2~10.1
- SuSE 8.2~9.2 - SuSE 8.2~9.2
Mac OS 8.6~9.2 / 10.1~10.4 Mac OS 8.6~9.2 / 10.1~10.4
WHQL Windows 2000, XP, 2003 Server, Windows 2000, XP, 2003 Server,
Vista 32/64bits) Vista 32/64bits)
Compatibility SPL & PCL6 : Win 2000/XP 32/64bits)/ SPL & PCL6 : Win 2000/XP 32/64bits)/
2003 server/Vista 32/64bits) 2003 server/Vista 32/64bits)
PS3: Win 2000/XP 32/64bits)/ PS3: Win 2000/XP 32/64bits)/
Vista 32/64bits)/ Vista 32/64bits)/
2003 PPD, Mac PPD, Linux PPD 2003 PPD, Mac PPD, Linux PPD
Wired Network Protocol N/A SPX/IPX, TCP/IP, Ethertalk, SNMP, HTTP 1.1
Supporting OS N/A Windows NT4.0/2000/XP 32/64bits)/2003
Server/Vista 32/64bits)NetWare 5.x, 6.x
Mac OS 8.6~9.2, 10.1~10.4
Various Linux OS including Red Hat 8~9,
Fedora Core 1~4, Mandrake 9.2~10.1, and
SuSE 8.2~9.2Unix HP-UX
Wireless Network Protocol N/A N/A
Supporting OS N/A N/A
Application Smart Panel SmartPanel for Windows/ Macintosh/LINUX SmartPanel for Windows/ Macintosh/LINUX
Printer Setting PSU for Windows/ Macintosh/LINUX PSU for Windows/ Macintosh/LINUX
Network Management N/A SyncThru Web Admin Service 4.0
IP Setting N/A SetIP
Interface
Parallel - N/A N/A
USB - Hi-Speed USB 2.0 Hi-Speed USB 2.0
Wired Network - N/A Ethernet 10/100 Base TX Internal)
Wireless Network - N/A N/A
User Interface
LCD - N/A N/A
LED - 2 LED, 1 Key 2 LED, 1 Key
Key - 1 Key Demo, Stop) 1 Key Demo, Stop)

Service Manual
Product spec and feature
2-3
Samsung Electronics
2.1.2.3 Paper Han ling
ITEM ML-2850D ML-2851ND
Standard Capacity - 250-sheet Cassette Tray, 1-sheet Multi 250-sheet Cassette Tray, 1-sheet Multi
Purpose Tray @80g/ Purpose Tray @80g/
Max. Capacity - 501 sheets @ 80g/ 501 sheets @ 80g/
Printing Max. Size 216 x 356 mm 8.5" x 14") 216 x 356 mm 8.5" x 14")
Min. Size 76 x 127 mm 3.0" x 5.0") 76 x 127 mm 3.0" x 5.0")
Multi-purpose tray
Capacity Plain Paper 1 sheets @ 80g/ 1 sheets @ 80g/
Envelope 1 sheets @75g/ 1 sheets @75g/
Media sizes - A4, A5, A6, Letter, Legal, Folio, Oficio, A4, A5, A6, Letter, Legal, Folio, Oficio,
Executive,ISO B5, JIS B5, 3"x5", Monarch, Executive,ISO B5, JIS B5, 3"x5", Monarch,
No.10, DL, C5, C6 No.10, DL, C5, C6
Media type - Plain Paper, Transparency, Envelope, Plain Paper, Transparency, Envelope,
Labels, Post Card, Card stock Labels, Post Card, Card stock
Media weight - 16~43lb 60 to 163g/ ) 16~43lb 60 to 163g/ )
Sensing - N/A N/A
Standard Cassette Tray
Capacity - 250 sheets @ 80g/ 250 sheets @ 80g/
Media sizes - A4, A5, Letter, Legal, Executive, Folio, A4, A5, Letter, Legal, Executive, Folio,
Oficio, ISO B5, JIS B5 Oficio, ISO B5, JIS B5
Media types - Plain paper Plain paper
Media weight - 16~28lb 60 to 105g/ ) 16~28lb 60 to 105g/ )
Sensing - Paper empty sensor Paper empty sensor
Optional Cassette Tray
Capacity - 250 sheets @ 80g/ 250 sheets @ 80g/
Media sizes - A4, A5, Letter, Legal, Executive, Folio, A4, A5, Letter, Legal, Executive, Folio,
Oficio, ISO B5, JIS B5 Oficio, ISO B5, JIS B5
Media types - Plain paper Plain paper
Media weight - 16~28lb 60 to 105g/ ) 16~28lb 60 to 105g/ )
Sensing - Paper empty sensor Paper empty sensor
Output Stacking
Capacity Face-Down 150 sheets @ 75g/ 150 sheets @ 75g/
Face-Up N/A N/A
Output Full sensing - N/A N/A
Duplex
Supporting - Built-in Built-in
Media sizes - A4, Letter, Legal, Folio, Oficio A4, Letter, Legal, Folio, Oficio
Media types - Plain Paper Plain Paper
Media weight - 20~24lb 75 to 90g/ ) 20~24lb 75 to 90g/ )
Printable Area
Non-Printable Area Envelope 10mm 0.4") from edge Top, Bottom, Left, 10mm 0.4") from edge Top, Bottom, Left,
Right) Right)
Other Media 4mm 0.16") from edge Top, Bottom, Left, 4mm 0.16") from edge Top, Bottom, Left,
Right) Right)

Service Manual
Product spec and feature
2-4
Samsung Electronics
2.1.2.5 Reliability & Service
2.1.2.4 Consumables
ITEM ML-2850D ML-2851ND
Toner Black Standard: Average Cartridge Yield 2K Standard: Average Cartridge Yield 2K
standard pages. standard pages.
High Yield: Average cartridge Yield 5K High Yield: Average cartridge Yield 5K
standard pages. standard pages.
Declared cartridge yield in accordance with Declared cartridge yield in accordance with
ISO/IEC 19752. ISO/IEC 19752.
Key Electronic key CRUM) Only Electronic key CRUM) Only
Life detect Toner gauge sensor by dot count Toner gauge sensor by dot count
Drum Yield N/A N/A
ITEM ML-2850D ML-2851ND
Max. Monthly Duty-50,000 sheets50,000 sheets
MPBF - 35,000 sheets 35,000 sheets
MTTR - 30 min. 30 min.
SET Life Cycle - 100,000 sheets or 5 years 100,000 sheets or 5 years
whichever comes first) whichever comes first)
RDS Comm. Mode Yes Yes
Operation Yes Yes
2.1.2.6 Environment
ITEM ML-2850D ML-2851ND
Operating Temperature 10C to 32C 10C to 32C
Environment Humidity 20% to 80% 20% to 80%
Acoustic Noise Printing Less than 50dBA Less than 50dBA
Level Sound Standby Less than 26.0 dBA Less than 26.0 dBA
Power/Pressure) Sleep Back Ground Level Back Ground Level
Power Consumption Ready Less than 60W Less than 60W
AVG. Less than 400W Less than 400W
Sleep / Power Off Less than 8W / Less than 0.4W Less than 8W / Less than 0.4W
Conformity to EPA) Conformity to EPA)
Dimension SET 364 x 369 x 209.6 mm 364 x 369 x 209.6 mm
W x D x H) 14.33" x 14.523" x 8.25 ") 14.33" x 14.523" x 8.25 ")
Weight SET 7.87 Kg 7.87 Kg

Service Manual
Product spec and feature
2-5
Samsung Electronics
2.1.2.8 Options
2.1.2.7 Packing & Accessory
ITEM ML-2850D ML-2851ND
In-Box - Driver & Network Install CD-ROM Driver & Network Install CD-ROM
Power Cable Power Cable
USB Cable CIS/China/Korea/India) USB Cable CIS/China/Korea/India)
Quick Install Guide Quick Install Guide
Warranty Registration Card Warranty Registration Card
User's Manual PDF File) User's Manual PDF File)
ITEM ML-2850D ML-2851ND
Memory Option 128MB) Option 128MB)
Second Cassette - 250-sheet Cassette Tray 250-sheet Cassette Tray
Wired Network - N/A N/A Built-in)
Wireless Network - N/A N/A
Hard Disk - N/A N/A
Duplex Unit - Standard Standard
2.1.2.9 Others
ITEM ML-2850D ML-2851ND
Memory Upgradable Mem. Slot N/A N/A
Upgradable Mem. Type N/A N/A
Upgradable Mem. Unit128MB option) 128MB option)
Sensor Paper Empty YES YES
Paper Size NO NO
Media Type NO NO
Paper Full NO NO
Service Service Item & Period 1. Transfer Roller : 50K pages 1. Transfer Roller : 50K pages
2. Fuser Unit : 50K pages 2. Fuser Unit : 50K pages
3. Pick-up Roller : 50K pages 3. Pick-up Roller : 50K pages
Certification Power FCC Part 15 Class B FCC Part 15 Class B
ICES-003 ICES-003
EN55022 Class B EN55022 Class B
Performance Jam Rate Base Line Paper : 1/5K Base Line Paper : 1/5K
Standard Paper : 1/2.5K Standard Paper : 1/2.5K
Stress Paper : 1/1500 Stress Paper : 1/1500
Speed Be equal or better than E250DN Be equal or better than E250DN
Resolution Be equal or better than E250DN Be equal or better than E250DN

Service Manual
Product spec and feature
2-6
Samsung Electronics
2.1.2.10 Reliability & Service
* Perio ic Replacing Parts
JC96-04717A(220V)
JC96-04718A(110V)
JC97-03062A
JC66-01218A
Code Fig.
50,000Fuser nit3
50,000Pick-up Roller2
50,000Transfer Roller1
Yield (pages)PartsNo. Code Fig. Yield (pages)PartsNo.

Service Manual
Product spec and feature
2-7
Samsung Electronics
2.1.3 Mo el Comparison Table
2.1.3.1 SEC Mo el
Samsung Samsung
ML-2851ND ML-2250
Image
Print Speed 28 ppm/A4 20 ppm/A4
Resolution 1,200 dpi class 600 dpi class
Processor 400 MHz 166 MHz
Memory Max.) 32 MB 160 MB) 16 MB 144 MB)
Emulation PCL6, PS3 PCL6
Interface USB 2.0, N/W USB 2.0, N/W IEEE1284
Paper Input 150 CST 150 CST
FPOT C/M) 30 sec/8.5 sec 50 sec/10 sec
Noise 50 dBA 51 dBA
Toner 2K/5K 3K/5K
Dim. WDH) 364 x 369 x 209.6mm 358 x 452 x 278mm
Options 250 SCF, Memory factory option) 250 SCF, Memory

Service Manual
Product spec and feature
2-8
Samsung Electronics
2.1.3.2 Competitor Mo el
Samsung Brother Lexmark
ML-2851ND HL-5240 E250D
Image
Print Speed 28 ppm/A4 30 ppm/Ltr 30 ppm/Ltr
Resolution 1,200 dpi class 1,200 dpi class 600 x 600 dpi
Processor 400 MHz 264 MHz 300 MHz
Memory Max.) 32 MB 160 MB) 16 MB 16 MB) 64 MB 576 MB)
Emulation PCL6,PS3 PCL6,PS3 PCL6,PS3
Interface USB 2.0, N/W USB 2.0, N/W USB 2.0, N/W
Paper Input 250 CST 250 OT 250 CST
FPOT C/M) 30 sec/8.5 sec 20 sec N/A
Noise 50 dBA 47 dBA N/A
Toner 2K/5K 2K/2.5K 1K/2K
Dim. WDH) 364 x 369 x 209.6mm 407 x 453 x 370mm 420 x 424 x 432mm
Options 250 SCF, 250 SCF 250/500 SCF,
Memory factory option) Memory

Service Manual
Product spec and feature
2-9
Samsung Electronics
2.2 Summary of Pro uct
This chapter describes the functions and operating principal of the main component.
2.2.1 Printer Components
2.2.1.1 Front View
* The figure above shows an ML-2851ND.
1 output tray 6 tray 1
2 control panel 7 optional tray 2
3 control board cover 8 paper level indicator
4 front cover 9 output support
5 manual tray 10 manual tray paper width guides

Service Manual
Product spec and feature
2-10
Samsung Electronics
2.2.1.2 Rear View
* The figure above shows an ML-2851ND.
1 network porta4 duplex unit
2 USB port 5 power receptacle
3 optional tray 2 cable connector 6 power switch
a. ML-2851ND only.